Buoyant and oil-proof india-rubber



7 s H rubber being not used.

Patented dannfil, W343 UNITED; STATES PATENT, OFFICE BUOYANT AND OIL-PROOF INDIA-RUBBER No Drawing.

This invention relates to an improvement in india-rubber and has for its object to pro duce a buoyant and oil-proof india-rubber composition adapted for the use in manufacturing articles adapted to float in water and proof against deterioration by mineral oil.

India-rubber as hitherto known of which various articles are manufactured is composed of raw rubber and such inorganic solid 10 substanceas zinc white, carbonate of lime and sulphate of barium intermixed with the said raw rubber. This india-rubber is buoyant in the water by itself without the addition of buoyant means, the specific gravity being i about 1.5-2.0, and is also liable to be affected by mineral oil. As far as my knowledge goes, no buoyant and oil-proof india-rubber has hitherto been proposed. v ,7 Itis desirable to obtain a buoyant and oilproof india-rubber for use-in manufacturin such articles as india-rubber-lrofi' for trans: ferring ful oilo n the water, and this'i'n'viition is proposed for the purpose. 7 The india-rubber according to this invention consists of raw rubber, factis, sulphur, alkaline soap"'insoluble in mineral. oil and having a. comparative low melting temperature and diphenyl-guanidine, intermixed 'with the said raw rubber, such inorganic solid 0 substances as are used in ordinary india- The alkaline soap functions to give buoyant and oil-proof character to the india-rubber, melting ata vulcanizing temperature of about 290 Fahr. and spreading about thoroughly and intimatelyin the tissue of the india-rubber.

My india-rubber composes in about the following proport-ionsviz, eighty-eightper cent or more of raw rubber, three per cent or lesfif factisyfive per cent or less of sulphur,

three per cent or less of alkaline soap such as for example, potassium soap, sodium soap, ammonia soap, and their mixtures, and one per cent or less of diphenyl-guanidine,

In preparing the-india-rubber, raw rubber is washed and dried and kneaded for about forty minutes by means of a kneading-roll, after which, the said factis, sulphur, alkalin'e soap and diphenyl-guanidine being added thereto one after another. The rubber is Application filed May 9, 1927'. Serial No. 190,143.

kneaded again by means of a kneading-roll heated by steam at about twenty pounds pressure. This kneaded *material is then molded into any desired shape and subjected to the action of a suitable hot-press and also vulcanized in well-known manner.

Thus prepared india-rubber will float in the water, the specific gravity beingabout 0.9, and is'proof against being afi'ected by mineral oil" on account of the existence of the intermixed alkaline soap, and moreover it is lesssubject to climatic conditions and is more flexible and strong in comparison with the ordinary india-rubber. Oil hose made of the india-rubber composition according to this invention is not only buoyant in the water by itself without any buoys or other flotation devices,rbut is not liable to be deformed even when piled up on board of a'tank-ship, and

out themsua'hspirahspringbifigrpFlifil thereto as in the said ordinary india-rubber hose," and it may consequently be easily handled. c

Having now particularly described and as- I, certained the nature of the said invention,

and in what manner the same is to beperformed, I declare that what I claim is:

A buoyant, and oil-proof india-rubber composition comprising the following ingredients intermixed in approximately the proportions stated, raw-rubber 88%, factis 3%, sulphur 5%, alkaline soap 3% and diphenylguanidine 1%.

In testimony whereof I have signed my name to this specification.

EIZO YOSHIOKA. 

